fix: broken docs link (#2163)

packages/website/pages/docs/concepts/car-files.md

@@ -353,6 +353,7 @@ You may already be using `dag-cbor` without knowing it! When using the client li
 
 
 
+[howto-store]: https://nft.storage/docs/how-to/mint-custom-metadata/
 [reference-client-library]: https://nftstorage.github.io/nft.storage/client/
 [reference-http-api]: https://nft.storage/api-docs/
 [github-ipfs-car]: https://github.com/web3-storage/ipfs-car
@@ -361,4 +362,4 @@ You may already be using `dag-cbor` without knowing it! When using the client li
 [ipfs-docs-dag-import]: https://docs.ipfs.io/reference/cli/#ipfs-dag-import
 [ipfs-docs-dag-get]: https://docs.ipfs.io/reference/cli/#ipfs-dag-get
 [car-spec]: https://ipld.io/specs/transport/car/
-[wikipedia-tar]: https://en.wikipedia.org/wiki/Tar_(computing)
+[wikipedia-tar]: https://en.wikipedia.org/wiki/Tar_(computing)